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                        Python高级
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                            <b>1.</b>
                        
                        Python语法高级专题1
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                            <b>1.1.</b>
                        
                        GIL问题
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                            <b>1.2.</b>
                        
                        赋值-浅拷贝-深拷贝
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                            <b>1.3.</b>
                        
                        import导入模块
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                            <b>1.4.</b>
                        
                        总结
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                            <b>2.</b>
                        
                        Python语法高级专题2
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                        多继承和MRO顺序
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                            <b>2.2.</b>
                        
                        property属性
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                            <b>2.3.</b>
                        
                        魔法属性和方法
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                            <b>2.4.</b>
                        
                        with管理上下文
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                            <b>2.5.</b>
                        
                        总结
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                            <b>3.</b>
                        
                        Python语法之装饰器
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                            <b>3.1.</b>
                        
                        闭包
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                            <b>3.2.</b>
                        
                        装饰器
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                            <b>3.3.</b>
                        
                        总结
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                            <b>4.</b>
                        
                        MySQL数据库基本操作
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                            <b>4.1.</b>
                        
                        数据库概述
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                            <b>4.2.</b>
                        
                        数据完整性
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                            <b>4.3.</b>
                        
                        图形化客户端Navicat
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                            <b>4.4.</b>
                        
                        命令行客户端SQL的使用
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                            <b>4.4.1.</b>
                        
                        登录和退出数据库
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                            <b>4.4.2.</b>
                        
                        表结构的操作
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                            <b>4.4.3.</b>
                        
                        数据库的操作
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                            <b>4.4.4.</b>
                        
                        表数据的操作
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                            <b>4.5.</b>
                        
                        知识总结
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                            <b>5.</b>
                        
                        MYSQL数据库进阶操作
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                            <b>5.1.</b>
                        
                        练习强化
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                            <b>5.2.</b>
                        
                        条件
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                            <b>5.3.</b>
                        
                        排序
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                            <b>5.4.</b>
                        
                        分页
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                            <b>5.5.</b>
                        
                        聚合函数
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                            <b>5.6.</b>
                        
                        分组
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                            <b>5.7.</b>
                        
                        连接
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                            <b>5.8.</b>
                        
                        自连接
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                            <b>5.9.</b>
                        
                        子查询
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                            <b>5.10.</b>
                        
                        总结
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                            <b>6.</b>
                        
                        MYSQL数据库编程
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                            <b>6.1.</b>
                        
                        数据准备
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                            <b>6.2.</b>
                        
                        SQL演练
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                            <b>6.3.</b>
                        
                        数据库设计
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                            <b>6.4.</b>
                        
                        数据库编程
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                            <b>6.5.</b>
                        
                        总结
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                            <b>7.</b>
                        
                        MySQL数据库高级用法
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                            <b>7.1.</b>
                        
                        视图
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                            <b>7.2.</b>
                        
                        事务
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                            <b>7.3.</b>
                        
                        索引
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                            <b>7.4.</b>
                        
                        用户管理
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                            <b>7.5.</b>
                        
                        主从配置
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                            <b>7.6.</b>
                        
                        总结
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                            <b>8.</b>
                        
                        miniweb框架
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                            <b>8.1.</b>
                        
                        框架概念
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                            <b>8.2.</b>
                        
                        实现一个简单的框架
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                            <b>8.3.</b>
                        
                        模板替换
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                            <b>8.4.</b>
                        
                        路由概念
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                            <b>8.5.</b>
                        
                        股票收藏夹
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                            <b>8.6.</b>
                        
                        复习
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<hr>
<h2 id="92-&#x5B50;&#x67E5;&#x8BE2;&#x6982;&#x5FF5;">9.2 &#x5B50;&#x67E5;&#x8BE2;&#x6982;&#x5FF5;</h2>
<p>&#x5728;&#x4E00;&#x4E2A; select &#x8BED;&#x53E5;&#x4E2D;,&#x5D4C;&#x5165;&#x4E86;&#x53E6;&#x5916;&#x4E00;&#x4E2A; select &#x8BED;&#x53E5;, &#x90A3;&#x4E48;&#x88AB;&#x5D4C;&#x5165;&#x7684; select &#x8BED;&#x53E5;&#x79F0;&#x4E4B;&#x4E3A;&#x5B50;&#x67E5;&#x8BE2;&#x8BED;&#x53E5;,&#x5916;&#x90E8;&#x90A3;&#x4E2A;select&#x8BED;&#x53E5;&#x5219;&#x79F0;&#x4E3A;&#x4E3B;&#x67E5;&#x8BE2;.</p>
<blockquote>
<p>&#x4E3B;&#x67E5;&#x8BE2;&#x548C;&#x5B50;&#x67E5;&#x8BE2;&#x7684;&#x5173;&#x7CFB;</p>
</blockquote>
<ul>
<li>&#x5B50;&#x67E5;&#x8BE2;&#x662F;&#x5D4C;&#x5165;&#x5230;&#x4E3B;&#x67E5;&#x8BE2;&#x4E2D;</li>
<li>&#x5B50;&#x67E5;&#x8BE2;&#x662F;&#x8F85;&#x52A9;&#x4E3B;&#x67E5;&#x8BE2;&#x7684;,&#x8981;&#x4E48;&#x5145;&#x5F53;&#x6761;&#x4EF6;,&#x8981;&#x4E48;&#x5145;&#x5F53;&#x6570;&#x636E;&#x6E90;</li>
<li>&#x5B50;&#x67E5;&#x8BE2;&#x662F;&#x53EF;&#x4EE5;&#x72EC;&#x7ACB;&#x5B58;&#x5728;&#x7684;&#x8BED;&#x53E5;,&#x662F;&#x4E00;&#x6761;&#x5B8C;&#x6574;&#x7684; select &#x8BED;&#x53E5;</li>
</ul>
<h2 id="93-&#x5B50;&#x67E5;&#x8BE2;&#x4F7F;&#x7528;">9.3 &#x5B50;&#x67E5;&#x8BE2;&#x4F7F;&#x7528;</h2>
<h3 id="931-&#x5206;&#x7C7B;">9.3.1 &#x5206;&#x7C7B;</h3>
<ul>
<li>&#x6807;&#x91CF;&#x5B50;&#x67E5;&#x8BE2;: &#x5B50;&#x67E5;&#x8BE2;&#x8FD4;&#x56DE;&#x7684;&#x7ED3;&#x679C;&#x662F;&#x4E00;&#x4E2A;&#x6570;&#x636E;(&#x4E00;&#x884C;&#x4E00;&#x5217;)</li>
<li>&#x5217;&#x5B50;&#x67E5;&#x8BE2;: &#x8FD4;&#x56DE;&#x7684;&#x7ED3;&#x679C;&#x662F;&#x4E00;&#x5217;(&#x4E00;&#x5217;&#x591A;&#x884C;)</li>
<li>&#x884C;&#x5B50;&#x67E5;&#x8BE2;: &#x8FD4;&#x56DE;&#x7684;&#x7ED3;&#x679C;&#x662F;&#x4E00;&#x884C;(&#x4E00;&#x884C;&#x591A;&#x5217;)</li>
</ul>
<h3 id="932-&#x6807;&#x91CF;&#x5B50;&#x67E5;&#x8BE2;">9.3.2 &#x6807;&#x91CF;&#x5B50;&#x67E5;&#x8BE2;</h3>
<ol>
<li>&#x67E5;&#x8BE2;&#x73ED;&#x7EA7;&#x5B66;&#x751F;&#x5E73;&#x5747;&#x5E74;&#x9F84;</li>
<li>&#x67E5;&#x8BE2;&#x5927;&#x4E8E;&#x5E73;&#x5747;&#x5E74;&#x9F84;&#x7684;&#x5B66;&#x751F;</li>
</ol>
<p>&#x67E5;&#x8BE2;&#x73ED;&#x7EA7;&#x5B66;&#x751F;&#x7684;&#x5E73;&#x5747;&#x8EAB;&#x9AD8;</p>
<pre><code class="lang-sql"><span class="hljs-operator"><span class="hljs-keyword">select</span> * <span class="hljs-keyword">from</span> students <span class="hljs-keyword">where</span> age &gt; (<span class="hljs-keyword">select</span> <span class="hljs-keyword">avg</span>(age) <span class="hljs-keyword">from</span> students);</span>
</code></pre>
<h3 id="933-&#x5217;&#x7EA7;&#x5B50;&#x67E5;&#x8BE2;">9.3.3 &#x5217;&#x7EA7;&#x5B50;&#x67E5;&#x8BE2;</h3>
<ul>
<li>&#x67E5;&#x8BE2;&#x8FD8;&#x6709;&#x5B66;&#x751F;&#x5728;&#x73ED;&#x7684;&#x6240;&#x6709;&#x73ED;&#x7EA7;&#x540D;&#x5B57;</li>
<li><ol>
<li>&#x627E;&#x51FA;&#x5B66;&#x751F;&#x8868;&#x4E2D;&#x6240;&#x6709;&#x7684;&#x73ED;&#x7EA7; id</li>
<li>&#x627E;&#x51FA;&#x73ED;&#x7EA7;&#x8868;&#x4E2D;&#x5BF9;&#x5E94;&#x7684;&#x540D;&#x5B57;</li>
</ol>
</li>
</ul>
<pre><code class="lang-sql"><span class="hljs-operator"><span class="hljs-keyword">select</span> <span class="hljs-keyword">name</span> <span class="hljs-keyword">from</span> classes <span class="hljs-keyword">where</span> <span class="hljs-keyword">id</span> <span class="hljs-keyword">in</span> (<span class="hljs-keyword">select</span> cls_id <span class="hljs-keyword">from</span> students);</span>
</code></pre>
<h3 id="934-&#x884C;&#x7EA7;&#x5B50;&#x67E5;&#x8BE2;">9.3.4 &#x884C;&#x7EA7;&#x5B50;&#x67E5;&#x8BE2;</h3>
<ul>
<li>&#x9700;&#x6C42;: &#x67E5;&#x627E;&#x73ED;&#x7EA7;&#x5E74;&#x9F84;&#x6700;&#x5927;,&#x8EAB;&#x9AD8;&#x6700;&#x9AD8;&#x7684;&#x5B66;&#x751F;</li>
<li>&#x884C;&#x5143;&#x7D20;: &#x5C06;&#x591A;&#x4E2A;&#x5B57;&#x6BB5;&#x5408;&#x6210;&#x4E00;&#x4E2A;&#x884C;&#x5143;&#x7D20;,&#x5728;&#x884C;&#x7EA7;&#x5B50;&#x67E5;&#x8BE2;&#x4E2D;&#x4F1A;&#x4F7F;&#x7528;&#x5230;&#x884C;&#x5143;&#x7D20;</li>
</ul>
<pre><code class="lang-sql"><span class="hljs-operator"><span class="hljs-keyword">select</span> * <span class="hljs-keyword">from</span> students <span class="hljs-keyword">where</span> (height,age) = (<span class="hljs-keyword">select</span> <span class="hljs-keyword">max</span>(height),<span class="hljs-keyword">max</span>(age) <span class="hljs-keyword">from</span> students);</span>
</code></pre>
<h2 id="94-&#x603B;&#x7ED3;">9.4 &#x603B;&#x7ED3;</h2>
<ol>
<li>&#x5B50;&#x67E5;&#x8BE2;&#x662F;&#x4E00;&#x4E2A;&#x5B8C;&#x6574;&#x7684;SQL&#x8BED;&#x53E5;</li>
<li>&#x5B50;&#x67E5;&#x8BE2;&#x5206;&#x4E3A;&#x4E09;&#x79CD; &#x6807;&#x91CF;&#x3001;&#x884C;&#x3001;&#x5217;&#x5B50;&#x67E5;&#x8BE2;</li>
<li>&#x6807;&#x91CF;&#x5B50;&#x67E5;&#x8BE2;&#x8FD4;&#x56DE;&#x7684;&#x7ED3;&#x679C;&#x4E00;&#x884C;&#x4E00;&#x5217;</li>
<li>&#x5217;&#x5B50;&#x67E5;&#x8BE2;&#x4F7F;&#x7528;&#x683C;&#x5F0F;: &#x4E3B;&#x67E5;&#x8BE2; where &#x6761;&#x4EF6; in (&#x5217;&#x5B50;&#x67E5;&#x8BE2;)</li>
<li>&#x884C;&#x5B50;&#x67E5;&#x8BE2;&#x4F7F;&#x7528;&#x683C;&#x5F0F;: &#x4E3B;&#x67E5;&#x8BE2; where (&#x5B57;&#x6BB5;1,2,...) = (&#x884C;&#x5B50;&#x67E5;&#x8BE2;)</li>
</ol>

                    
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